Anuran Species Composition of an Impacted Seasonal Lake in Sapele, Delta State, Nigeria.

Abstract

Studies on anuran diversity in Lake Akapankpan, a seasonal Lake in Sapele, Delta State was carried out between May and October 2011. Human activities around the Lake included its use as a dumpsite and as a receptor for run-offs from mechanic activities located some few metres from it. Six anuran species which included Hoplobatrachus occipitalis, Ptychadena bibroni, P. pumilio, P. mascareniensis, Amietophyrnus (Bufo)maculatus and Afrixalus dorsalis were recorded from the Lake. Ptychadena pumilio was the most abundant species (49%) while Afrixalus dorsalis and Hoplobatrachus occipitalis were least (4%). Species diversity was low (Hꞌ = 1.37). Physico-chemical parameters of the water showed iron to be high (P<0.05). Statistical analysis was done using the one sample test. Although there are no baseline studies on the Lake, studies on similar ecological areas in Sapele showed a higher diversity (Hꞌ = 1.70). Silurana tropicalis, a completely aquatic species commonly found in waters was absent while another aquatic species Hoplobatrachus occipitalis commonly recorded in high numbers in waters recorded only 4%. There is a possibility that the low species diversity recorded could be due to the impact of human activities around the Lake. The need to minimize human activities around water bodies is highly recommended to reduce species loss and ultimately, amphibian decline.

Keywords: anuran diversity, impacted seasonal Lake, species loss, amphibian decline